Aversive respondent conditioning: Effects of different intervals of CS presentation during extinction on the ressurgence of the CR

Author(s)

Pedro Fonseca Zuccolo

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Psicologia (IP/SBD)
• Defense date: 2014-05-28

Examining board members

Maria Helena Leite Hunziker; Roberto Alves Banaco; François Jacques Tonneau

• Advisor: Maria Helena Leite Hunziker

Abstract

Research on respondent conditioning involving aversive stimuli have shown that conditional responses (CRs) may reappear after extinction. Schiller et al., (2010) have demonstrated that CR inhibition may be long-lasting if there is a longer interval between the first and the remaining presentations of the CS during extinction. This research aimed at replicating the previously described experiment as a way of starting a series of investigations on respondent extinction in the Biobehavioral Analysis Laboratory (LABC). We recruited 11 adult participants who were exposed to a mild electrical stimulation (US) and were shown three colored squares (CSs). Skin conductance responses during US and CS presentations were used as measures of URs and CRs, respectively. The subjects were divided into two groups (experimental and control) and went through three consecutive stages separated by a 24 hr interval: conditioning, extinction, and ressurgence test. These groups differed from each other only regarding the treatment received during extinction. In conditioning, two stimuli were paired with the CS (CSa+ and CSb+) while a third stimulus was never paired with the US. In the extinction phase, participants were exposed to the three CSs without the US. There was a 10 min interval between the first and the remaining presentations of the CSa+ only for the experimental group. In the test phase, the US was administered four times, which was followed by a 10 min interval and sucessive presentations of all CSs without the US. In average, groups did not differ from each other, presenting equivalent levels of conditioning, extinction, and an increase in CR amplitudes following presentation of all stimuli in the test phase. However, we observed significant between-subject variability within both groups: besides presenting different patterns of conditioning and extinction, not every subject showed CR ressurgence. These data do not replicate the findings reported by Schiller et al. (2010), suggesting that further analysis are needed to identify variables that control conditioning and extinction (AU)

• FAPESP's process: 11/16088-9 - Aversive respondent conditioning: effects of CS presentation during extinction on the ressurgence of the Cr
• Grantee: Pedro Fonseca Zuccolo
• Support Opportunities: Scholarships in Brazil - Master